Booster steering device



y 2, Q G. a. ARMINGTON E 03,325

BOOSTER STEERING DEVICE .Origihal FiIed Feb. 4, 1942 s Sheets-Sheet, '1

FIG-2 ATTORNEY July 2, 1946. s. E. ARMlNGTON BOOSTER STEERING DEVICE IOriginal Filed Fb. 4, 1942 s Sheets-Sheet 3 INVENTOR C0RGE E. ARMlNGTONATTORNEYS member.

Patented July 2, 1946 UNITED STATES PATENT OFFICE.

BOOSTER STEERING DEVICE George E. Armington, South Euclid, Ohio, as-

signor to The Euclid Road Machinery Co., Euclid, Ohio, a corporation ofOhio Continuation of application Serial No. 429,557,

February 4, 1942.

' 1945, Serial No. 587,365

This invention relates to improvements in power steering devices of thetype wherein the usual steering member is operated to effect movement ofa lead valve which places in operation a booster device which normallytakes over most of the heavy work connected with the movement of theparts to be steered.

This application is a continuation of my earlier application for Boostersteering device, Serial No. 429,557, filed February 4, 1942.

One of the features of the present invention is the provision of acylinder and piston booster motor with valve mechanism for operating thesame which is adapted to be operated by the differential pressureexerted between the'inlet and outlet of the deviceso that a movingstream of oil or other pressure fluid impelled by a pump may traversethe booster device and pass on to other fluid actuated power mechanismon the vehicle to perform other work before returning to the pump.

Another object of the present invention is to provide a device of thetype described wherein provision, is made for relief of excessivepressure if such should occur and provision is also made for relief ofpressure from the hydraulic system generally if it is necessary tooperate the steering device by hand in the case of failure of the pumpto supply sufficient pressure for power steering.-

Another object of the present invention is to provide improvements inremote controlled steering devices of this sort wherein the parts of asecondary system move in response to the parts of a primary system whichin turn are directly under the control of the usual vehicle steeringThis permits the placing of the parts in the secondary system at. themost convenient point for operating the parts of the vehicle which mustbe moved to steer the same. In such remote controlled steering devicesthe present invention provides means for keeping the secondary sys- 14Claims. (Cl.18079 .2)

tem filled with pressure fluid at all times, means for preventing theproduction of excessive pressures in the secondary system, and means forsynchronizing. the movement of the parts in the secondary system withthe parts in the primary system.

Other novel features and advantages of my improved device will beapparent from the accompanying drawings and description, and theessential features thereof will be set forth in the claims. Y

In the drawings:

Fig. 1 is a side elevation of a scraper equipped with my improvedsteering device;

This application April 9,

Fig. 2 is an enlarged top plan view of the rear portion of the device ofFig. 1;

Fig. 3 is an enlarged central vertical section through thedoublecylinder device seen at the left in Fig. l; I

Fig. 4 is a transverse sectional view taken along the line l4 of Fig. 3;

Fig. 4a is a fragmental sectional view taken along the line H of Fig, 4;

Fig. 5 is a iragmental sectional view taken along the line 5--5 of Fig.4;

Fig. 6 is an end elevational view taken from the left end of Fig. 3;

Fig. 7 is a sectional view taken along 1-! of Fig.3;

Fig. 8 is an enlarged central horizontal section through the cylinder atthe right-hand end of Fig. 1; while Fig. 9 is a diagrammatic view-of thehydraulic system as a whole.

It will be understood by those skilled in this art that myimprovedsteering device may be applied to many different types of vehicles butfor the purposes of the present description it has been shown as appliedto a carrying scraper having a bowl ll whose front end is supported by atractor l2 and whose rear end is supported by a pair of steerable wheelsI3 suitably mounted on the'scraper frame M. The tractor is provided withan internal combustion engine connected by drive means (not shown) to apair of drive wheels IS.

The steering device disclosed herein is adapted for operation by theusual vehicle steering member such as the wheel l6 of the tractor.This'is connected through the usual steering column I! with the steeringpitman l8 as is well known in this art. A clevis I9 connects the pitmanwith the drag link 20. The forward end of the drag link is pivotallyconnected to the secondary pitman arm 2| intermediate the ends thereofby means of the pin 22. The upper end of this secondary pitman arm ispivotally connected at 23 to the forward end of piston rod 24. The lowerend of the pitman arm 2| carries a pin 25 which engages in elongatedslot 26a of the link 26. This link is pivotally connected at 21 to theframe of the tractor. On the-inner end of pin 25 is pivotally mountedthe valve control rod 28.

The function of the parts just described is well link 20 causes movementof arm 2| about the the line to'operate the control valve of the boostersteering device by movement of the valve control rod 28. Followingmovement of this valve the booster steering device moves 2 piston rod 24and produces movement of the steering wheels I3 as will be presentlydescribed until movement of arm 2| about the momentarily fixed pivot 22again causes centering of pin;25 in the slot 26a, whereupon the'valvecontrol rod 28 moves the valve to neutral position and the action of thebooster.

tion shown in Fig. 3 permits the flow of pressurefiuid from pipe 32through the inlet passageway 35, past the valve and through the outletpasv sageway 36 to the pipe 31.

Two positions of valve 34 are provided for directing the flow ofpressure fluid against one or the other of the faces of piston 29 asdesired, for steering the vehicle to the left or to the right. One ofthese positions is shown in Fig. 9 for steering the vehicle to theright. This establishes flow from the inlet pipe 32 to the passage 38which communicates with the right-hand face movement of rod 24 andpiston 29 as though power had been applied. This will produce thedesired steering action as will be presently described. However, suchaction would be almost impossible if the operator of the vehicle had toforce the fluid from cylinder 38 through the entire hydraulic system. Iffor instance the operator' is trying to move piston 29 toward the rightas viewed in Fig. 3, fluid will be forced through PIGS conduit 38, valve34, passageways 36 and 43, chamber 42, passageway 45, valves 44 and 34and then through passageway 39 to the left-hand end of cylinder 39.-Thus the fluid moves readily through the by-pass 44 and the operatorcan move piston 29 in either direction by manual operation of steeringwheel'l6.

The device thus far described could be used I for producing a directsteering effect by connecting. a steering drag link in any suitablemanner to move with rod 24. In the present instance, however, the deviceis shown adapted to produce a remote controlled steering effect whichwill now be described. v

The movement of piston 29 in cylinder38 is utilized to cause the desiredflow of a pressure fluid in a secondary system which in turn is directlyconnected to apparatus for steering of piston 29 as shown in the variousviews. This will move piston 29 toward the left and cause, discharge offluid from the left-hand end of cylinder 39 through conduit 39 andoutlet passage 36. The operating position for valve 34 for turning thevehicle toward the left is substantially at right angles to the positionin Fig. 9 and provides communication from inlet pipe 32 throughpassageway 39 to the left face of piston 29. Fluid then driven from theright end of cylinder 30 will pass through passageway 38 to outletpassageway 36.

Means is provided to relieve excessive pressure on the inlet side of thevalve as might occur for instance if the valve were set in one of itsoperating positions and it was impossible to move the parts. In suchcase the pump 3| might build up a very high pressure. The means providedforthis purpose includes the ball check valve (Fig. .3) which permitsflow from the inlet side to the outlet side of the valve 34 only. Thisball'is loaded by spring which is\adjusted to the desired pressure. Uponexcessive pressure above this predetermined point theball 40 will belifted from its seat against the action of spring 4| -and fluid willflow through chamber 42 and passageway 43 which leads to the outletpassageway36.

Means is provided permitting the comparativethe steering wheel l6 may beturned in the usual manner thus transmittingmotion to pitman l8, draglink 20 and arm 2|. The lower end of this arm being temporarily fixedthe .upper end of the arm will be moved thus causing the same wheels |3.In the form shown here a cylinder 46 is mounted in line with cylinder 30and both of these cylinders are suitably mounted on the tractor frame bymeans of one or more brackets 41. Piston 48 is mounted rigidly on rod 24for reciprocation 'in cylinder 46. The steering motor comprises acylinder 49 having a swivel mounting 49a on the rear scraper frame I4and provided with a reciprocating piston 5|! whose piston rod 5| ispivotally connected with a lever 52 which in turn is pivotally mountedat 53 on the frame M. The other end of lever 52 is connected withsteering arm 54 'for movement of wheel l3 which is properly mounted on astub axle and kingpin as is usual in such cases. The arm 54 of Fig. 2connects with the other wheel l3 through a link 54a. The rear end ofcylinder 46 is connected by conduit 55 with the forward end of .cylinder49. The forward end of cylinder 46 is connected by conduit 56 with therear end of cylinder 49. It is evident therefore that movement of piston48 rearwardly or toward the right as viewed in Figs. 3 and 9 will causerearward movement of piston 56 by forcingv fluid from the rear end ofcylinder 46 through conduit 55 to the forward end of cylinder 49. At thesame time the fluid forced out of the rear end of cylinder 49 will passthrough conduit 56 to the forward end of cylinder 46. Thuspiston 50follows the movements ofpiston 48.

A passageway-51 (Fig. 4) normally closed by tons 29, 48 and thesecondary piston 58.

If excessive pressure builds up in the secondary system it is relievedthrough passageway 60 (Fig. 5) in the partition wall 30;; betweencylinders 36 and 46, This passageway is normally closed by the ballcheck valve 6! loaded by spring 62 and permitting flow in one direction'only from the secondary system toward the primary system if excessivepressure build up in the secondar systezn as would occur for instance ifthe steering wheels were held against movement when the aponly. Thesevalves are normally held t their seats by the spring 66. A plunger 64aof valve 64 will strike the rear head casting of the cylinder when thepiston reaches the rear end of its travel so as to lift ball 64 from itsseat. In a like manner a plunger 55a of valve 55 will strike the for-Ward head casting of the'cylinder when the piston reaches the forwardend of its travel so as to lift ball 65 from its seat. It results fromthis constr *ction that as piston 59 in Fig. 8 moves to the right end ofits stroke, the plunger 550, will lift valve 65 from its seat slightly,and thereafter if excess pressure builds up on the left-hand faceexerted on each face of piston 29 and this tends of piston 50, thepressure fluid will lift valve 64 from its seat and fluid will beby-passed from conduit 58 through the piston to' conduit 55. Whenevernecessary to synchronize the position of pistons 48 and 50 it is'onlynecessary therefore to run piston 48 to one end of its stroke and eratorof the tractor,

As mentioned earlier, this power steering device I operates on adifferential pressure of the stream flowing from pump 3|; That is tosay, sufllcient pressure from this flowing stream is utilized to.

move piston 29 and the stream after accomplishing this work flowsthrough conduit 31 and is available for further work. For instanceconduit 31 may be connected to cylinders 61 through suitable controlvalves as for instance in a system shown in the copending application ofRaymond Q. Armington and myself, Serial Number 333,526, filed May 6,1940, now Patent Number 2,335,231, dated November 30, 1943. Referring toFig. 1, two parallel cylinders 61 acting through their piston rods 61aoscillate crank arms 14, torque rod 15 and crank arms 16 to raise andlower the forward end of the body ll relative to the tractor 12. Re-Ierring to Fig, 9 if valve 10 is turned degrees counter-clockwise fromthe position shown, pressure fluid will flow fromconduit 31 throughconduit H to move the pistons in motor 61 toward the left, thus causingliquid driven before the pistons to pass through conduit 12, valve 10and conduit 68 back to the pump. After performing this additional workthe pressure fluid may then return to pump 3i through conduit 83. Excessfluid in the system connected to lines 31 and 68 may return to the pumpthrough check valve 68. I have thus provided a means whereby a singlepump may be utilized for producing power steering 01 a vehicle throughthe utilization of a por-- tion of the pressure of the fluid stream andthereafter the residual energy in the fluid stream may 6 be utilized inother power devices to do other work connected with the operation of thevehicle.

The system-herein disclosed operates satisfactorily with a pump 3| ofeither large or small volume. Any desired volume of fluid may flow.through the booster steering device to the hydraulically operated devicebeyond it, The only limitation on such flow is the siz of ports in valve34. I

The fact that there is a large volume of oil or the like passing throughthe steering device tends to provide stability to the steering apparatusbecause'a certain head of oil pressure is to eliminate shimmy and takesthe shock off the steering gear.

Heavy back pressure in the line 37 does not seriously aiTect theoperation of the booster steering device as long as the total pressurerequired is within the capacity ofthe pump 3|. This is true because thesteering device operates on the differential in pressure between theincoming fluid in pipe 32 and the outgoing fluid in pipe 31.

It will be understood by those skilled in this art that the device heredisclosed is equally useful in other types of vehicles. vice might beused to steer a dump truck wherein a cylinder'similar to thatillustrated at 61 might be used for producing dumping action of thebody.

- What I claim is: I

1. A self-contained unitary power operating system for a vehicle havinga steering member, comprising a cylinder and piston motor, an operatingconnection from said motor to said steering member, a fluid operatedpower device on said' I vehicle, a pump, a pressure fluid conduitconnection from the discharge side of said pump to one face of saidpiston, a pressure fiuid conduitconnection from the other face of saidpiston to said fluid operated power device, and a fluid connec-' saidother face of said piston during said motor operation may be utilized insaid power device.

2. Steering means for a vehicle having steerable wheel means comprisinga cylinder and piston motor operatively connected with said wheel meansfor steering the latter, an operator controlled vehlcle steering member,a cylinder and piston motor, a primary pressure fluid supply system,valve means for directing fluid from said system selectively to oppositefaces of the piston of said last named motor, an operative connectionbetween said steering member and said valve for positioning the latter,athird cylinder and piston device movable in response to movements ofsaid second named motor, a closed fluid system including said firstnamed motor and said third device and including a conduit connecting oneend 01' said first motor with one end of said device and a conduitconnecting the other end of said first motor with the other end of-saiddevice, whereby fluid moved by said device will be forced to said firstmotor to actuate the same.

'3. The combination of claim 2 including valve controlled by-pass meansassociated withsaid first named motor and permitting fiuid flow from oneside to the other side of said piston of said first named motor, andmeans opening said by-pass means by relative approach. between saidpiston and either end oi. said cylinder of said I For instance the dc--flrst'named motor near the end of a stroke in either direction.

4. The combination of claim 2 including a bypass between said closedfluid system and said primary fluid supply system, valve means in saidby-pass permitting flow toward said primary system only, and meansbiasing said valve toward closed position.

5. The combination of claim 2 including a by- ,pass between said closedfluid system and said primary fluid supply system, and easily openablevalve means in said by-pass permitting flow toward said closed system'only.

6. A self-contained power operating system for a vehicle having asteering member, comprising a first cylinder and piston motor, anoperating. connection from said motor to said steering member, a powerdevice on said vehicle, a second cylinder and piston motor operativelyconnected with said power device, a pump, a pressure fluid conduitconnection from the discharge side of the other face of the piston ofsaid flrst motor to one face of the-piston, of said second motor, and afluid conduit connection from the other face of the piston of. saidsecond motor to the 1 intake side of said pump, whereby the' pressure offluid from said pump may be utilized in said first motor for steeringand the fluid dischargedfrom said other face of the piston of said firstmotor during said first motor operation may be utilized in said powerdevice.

'1. In a device of the class described, the combinatlon of adouble-acting cylinder and piston motor, a pump, a pressure fluid supplyconnection from the discharge side of said pump to said motor, valvemeans for selectively connecting said pressure fluid supply to eitherone of the ends of said motor to operate it in one direction or theother, a discharge conduit for the reception of pressure fluid from theother end of said said pump toone face of the piston of said firstmotor, a pressure fluid conduit connection from a valve for selectivelyconnecting one of said passageways to said pressure pipe whileconnecting the other of said passageways to said discharge pipe, anoperative connection from said other endof said lever to said valve toselect the desired position of said valve, a by-pass connecting saidpressure pipe and said discharge pipe, and a valve in said by-passpermitting flow from said discharge pipe to said pressure pipe only 9.Steering means for a vehicle having steerable wheel means, comprising amotor having cylinder and piston members one of which is movable,connecting means between said movable member and said steerable wheelmeans, a lever, an operative connection between said movable member andone end of said lever for moving said one end to follow movement of saidmovable member, an operator, controlled vehicle steering member, anoperative connection between said steering member and a point on saidlever intermediate its ends, a lost motion mounting for holding theother end of said lever relative to said vehicle, means for supplyingfluid to and away from said'motor including a' pump and a pressure pipeleading therefrom and two passageways leading'respectively to oppositesides of said piston member and a discharge pipe, and a valve forselectively connecting one of said passageways to said pressure pipe'while connecting the other of said passageways to said discharge pipe,an operative connection from said other end of said lever to said valveto select the desired position of said valve, a fluid operated deviceconnected with said discharge-pipe, and said valve having a neutralposition permitting flow from said pressure pipe directly to saiddischarge pipe, whereby said device may be operated in all positions ofsaid valve.

10. Steering means for a vehicle having steer-' able wheel means,comprising a motor having cylinder and piston members one of which ismovmotor set in motion by advancing movement of the piston of said motorwhen operated, said valve means having two motor-operating positions ineither of which it connects the other end of said motor withsaiddischarge conduit, said valve means having a neutral positionpermitting fluid flow directly from said supply to said dischargeconduit, steering means for turning said valve means, mechanismconnected with said valve means and with said motor for automaticallyreturning said valve means to neutral position by motor movement, and afluid power de- 1 vice connected with said discharge conduit, wherebysaid power device may be operated in all positions of said .valve means.

' 8. Steering means for a vehicle having steerable wheel means,comprising a moto having cylinder and piston members one of which ismovable, connecting means between said movable member and said steerablewheel means, a lever,

an operative connection between said movable said one end to followmovement of said movj able member. an operator controlled vehiclesteering member, an operative connection bee tween said steering memberand a point on said lever intermediate its ends, a lost motion mountingfor holding the other end of said lever relative to said vehicle, meansfor supplying fluid- 1 to and away from said motor includinga pump and apressure pipe leading therefrom and two able, connecting means betweensaid movable member and said steerable wheel means. a lever, anoperative connection between said movable member and one end of saidlever for moving said one end to follow movement of said movable member,an operator controlled vehicle steering member, an operative connectionbetween saidsteering member .and a point on said lever intervalve forselectively connecting one of said passageways to said pressure pipewhile connecting the other of said passageways to said discharge pipe,an operative connection from said other end of said lever to said-valveto select the desired position of said valve, a fluid operated deviceconnected with said discharge pipe, a by-pass member and one endof saidlever for moving passageways leading respectively to opposite sides ofsaid piston member and a discharge pipe and connecting said pressure {weand saiddischarge pipe, a valve in said by-pass permitting flow fromsaid pressure pipe to said discharge pipe only, means biasing said valveclosed against fluid pressure sufllclent for normal operation of saidmotor,

and said first named valve having a neutral position permitting flowfrom said pressure pipe directly to said dischargepipe, whereby saiddevice may be operated under allconditions.

l1. Steering means 'fora vehicle havingsteerable wheel means, comprisinga motor having cylinder and piston members one of which is movement ofthe former, means for conducting fluid to and away from said motorincluding a pump and a pressure pipe leading therefrom and mosses 13,Steering means re: a vehicle having steerable wheel means, comprising amotor having causing movement of the latter responsive to,

two passageways leading resp ctively to opposite sides of said pistonmember and a discharge pipe and a valve having two operating positionsin each of which 'it selectively connects one of said passageways tosaid pressure pipe while connecting the other of said passageways tosaid discharge pipe, said valve having a neutral position between itsoperative positions, an operator controlled vehicle steering member, anoperative connection; between said steering member and said valve,mechanism connected with said valve and with'said movable motor memberfor auto--- matically returning said valve to neutral position by, motormovement. a by-pass connecting said pressure pipe and said dischargepipe, and a valve in said by-pass permitting new from said dischargepipe to said pressure pipe only,

l2. Steering means for a vehicle having steerable wheel means,comprising a motor having cylinder and piston members one of which ismovable,- means operatively connecting said movable member and saidsteerable wheel means for causing movement 01' the latter responsive tobetween its operative positions, an-operator controlled vehicle steeringmember, an operative connection between said steering member and saidvalve, mechanism connected with saidvalve and with said movable motormember for automatically returningsaid-valve to neutral position bymotor movement, a fluid operated device connected with said dischargepipe, and said valve in its neutral position permitting flow from saidpressure pipe directly to said discharge pipe,

whereby said device may be operated in all positions of said valve v Ian operating connection from one of said motor cylinder and pistonmembers one of which is movable, means operatively connecting saidmovable member and said steerable wheel means forv causing movement ofthe latter responsive to movement of the former, means for conductingfluid-to and away from said motor including a pump and a pressure pipeleading therefrom and two passageways leading respectively to oppositesides of said piston member and a discharge pipe and a valve having twooperating positions in each of which it selectively connects one of saidpassageways to said pressure pipe while connecting the other of saidpassageways to said discharge pipe, said-valve having a neutral positionbetween its operative positions, an operator controlled vehicle steeringmember, an operative connection between said steering member and saidvalve, mechanism connected with said valve and with said movablemotor'member for automatically returning said valve to neutral positionby motor movement, a fluidoperated device connected with said dischargepipe, a by-Dass connecting said pressure pipe and said discharge pipe, avalve in said by-pass permitting flow from said pressure pipe to saiddischarge Pipe only, means biasing said valve closed against fluidpressure sumcient for normal operation 01' said motor, and said firstnamed valve in its neutral position permitting flow from said pressurepipe directly to said discharge pipe, whereby said device may beoperated under all conditions.

14. A self-contained unitary power operating system for a vehicle havinga steering member and a power operated member, comprising first andsecond cylinder and piston motor means,

mean to said steering member, an. operating pressure fluid conduitconnection from the dis- 1 charge side of said pump to one face of apiston of said first motor means, a valved pressure fluid conduitconnection from the other face of the v said piston of said first motormeans to one face of "a piston of said second motor means, and .a'

fluid connection from the other face of the said side of said pump.

piston of said second motor means to the" intake

